Temperature regulating water circulator for molding presses and other purposes



June 1952 etc. BECKER TEMPERATURE REGULATING WATER CIRCULATOR FORMOLDING PRESSES AND OTHER PURPOSES Filed May 16, 1950 2 SHEETS-SHEET 1DH [2M6] 17: 6/6/72? 6. Becker.

I QZ/f-W d llf l n June 3, 1952 G. c. BECKER TEMPERATURE REGULATINGWATER CIRCULATOR FOR MOLDING PRESSES AND OTHER PURPOSES 2 SHEETSSHEET 2Filed May 16, 1950 MUNEIUWE Wei/L2? 6? 5601671 Patented June 3, 1952UNITED" STATES PATENT OFFICE.

2,598,966 a TEMiERKTUR-E REGULATING ,WATER CIR- CULATOR FOR- MOLDINGPRES'SES AND OTHER PURPOSES Glenn 0. Becker, Chicago, 111., assignor toVacuum can Gomp'any, Chicago, 111., a corporation of Illinois 1 Thisinvention relates to a water heating and circulating device designed forthe purpose of supplying and circulating hot water to the molding diesemployed in molding plastic material,

2 Each of the tanks I and 2 hasasscciated therewith an electric motorI3, which drives a rotary water pump M having its intake port connectedto the bottom of the tank through a pipe I5.

but the equipment may have many other useful 5 The water is dischargedfrom the pump through applications, in general, in any situation where apipe l6, which has an end portion I'I projecttemperature is to becontrolled by a new of water ing out of the cabinet, which contains thetanks (or other liquid) heated to a predetermined temand other elementsof the apparatus. The perature. projecting end portion I! of the hotwater out- The main objects of the invention areto pro let pipe isthreaded for receiving suitable pipe vide a water-heating andcirculating device, or hose fittings, whereby this outlet pipe may bewhereby a substantially constant flow of hot connected to the inlet of amolding die water water may be maintained; to provide a water chamber orthe like. heating and circulating device whereby the tem- Cold water isadmitted into the bottom of perature of the water may be effectivelyregeach tank through the cold water inlet pipe 5 ulated and maintainedwithin a few degrees of a and the branch 6 or 1, previously referred to,predetermined temperature; to provide a device the pipe also having anend portion projecting of the character indicated which is portable sooutside of the cabinet to facilitate connection of that it may bereadily moved from one place to said inlet pipe to a source of coldwater. In noranother and which may be readily connected to maloperation, the tanks are'connected through and disconnected frommoldingpresses or other the inlet pipe 5 to a source of cold water underapparatus with which the device is associated; pressure which will tendto cause cold water to to provide a device of the character indicatedflow into said tanks to replace any water lost of compact form and smal1over-all size, but from the tanks or apparatus to which the device whichwill, nevertheless, provide adequate water is connected. Once the tanksand connected heating capacity for the purpose indicated; and apparatusare filled, the supply pressure has no to provide a device of thecharacter indicated, effect except to effect replacement of lost waterwhich will be low in cost of productionand opas just explained. Waterwhich is delivered to eration, while at the same time, being highly themolding die heating chamber or other appr tic l a effici t f r i p pparatus is returned to the tank from which it Ot er je ts a d a vanta esof the inventio came, through hot water inlet pipes I I or I2 for W b uM y reference o the follbwing the respective tanks and flows through'aconduit p fi a and mpa y drawings (two IB, a fitting I9, and a nipple 20into the top of sheets), wherein there 1s dlsclos'ed -a -Wa r the tank Ior 2. The hot water return pipes e and clrcillatme devlce embodyme aSelected II and [2 are each extended, as indicated at 2!, form of the fand connected to a valve 22 to which the branch the V, r 9 or branch I'Dof the discharge pipe 8 is con- Figure 1 1S a from Q' YaY P 9?? P nnected. This valve 22 is normally closed and woken WW shown Sectwntoreveal held closed by spring means enclosed in the celtgm i 3 y .7 v40 structure of the valve, and it is adapted to be Figure 2 1s arsldeView 9 9 plat? Opened by energization of a solenoid 23. The having beenremoved to clearly (11861058 par-ts or 1 mid 23 is in c1 dad in 61 t ith the structure enclosed within a cabinetwhich so 6 w u an e0 no lcontains most of the mechanism an ad ustable thermostat represented at24, The water heating and circulating device 1 2 t? gd gf 3 clpsmg of 2shown in the drawings is a double unit embodying e ec rm 011cm me u mg 68016mm w i a pair of tanks I and 2. These tanks I and 2 e thetemperature i flowmg may be made of stainless steel. or any? othersuitthrough the plpe I or back i we bank 1 able metal, and they are eachenclosed in outer 2 reaches Predetermmed' maxlmum containers 3 and aninsulating jacket 4 located ture' Operatmn of the mermostat f maybetween the inner containers-I and 2, respectively, be referred to as acoolmg thermostat, 15 and the Outer containers, Thetanks I trolled by athermostat bulb 25,, which is located are interconnected the agency of athe through the Water 001d Water 1; pipe 5 m has branches 5 flows in thecourse of its return to thetank I or 2. and 7 respectively leading tothe,bottom 0f th If the temperature of the return: water, should t k d 2thrgugh theaggncy fa disreach the maximum temperature-to which thecharge pipe 8, which has branches 9 and lllconthermostat 24 is set, thesolenoid '23 will be nected through suitable pipingto independentenergized a d Va ve 22 Opened, t y P hot water inlets II and -I 2-iorthe tanks I and 2 mitfing at least a p t o of the hot water torespectively. Except for the foregoing-connectflow through the valve 22into the discharge ing piping, the tanks 1 and 2 and other apparatusassociated with the respective tanks are, lindependent of each other.

line 8, thereby automatically permitting cold water to enter through.theinlet -5-:and branches 6 or 7 into the tank I or 2. By mixing fresh,cold water with the water contained in the tank, the temperature will,of course, be lowered. When the lowered temperature is reflected byaction on the thermostat bulb 25, the circuit to the solenoid 23 will,of course, be broken, permitting the solenoid to be automatically closedby the spring action above mentioned, whereupon the further escape ordischarge of hot water will be prevented and the return water directedback to the tank I or 2 for re-circulation.

Heating of the water contained in the tanks is effected by means of aplurality of electrical heating bands, indicated at 26, these bandsbeing located at more or less uniformly spaced locations along thelength of the tank, so as to thereby effectively distribute the heatgenerated in these heating bands. These heating bands may be of anysuitable electrical construction, the details of which are known and nota part of the present invention.

All of the heating bands 26 on one tank are interconnected and anelectric circuit to such heating bands is controlled by a thermostat 21,which is connected to a thermostat bulb 28 located in the tank. Thisbulb has a stem extending upwardly through the fitting 19, whereby thebulb is suspended in the proper location in the tank (preferablyapproximately midway between the top and bottom of the tank), and theusual tube connection between the bulb and the thermostat extends out ofthe upper end of the fitting, as indicated at 29, such connectionextending to the thermostat 27 in the usual manner. The thermostat 21 isadjustable so that it may be set for any selected temperature within apredetermined range. This thermostat is normally adjusted to apredetermined, minimum temperature so that when the temperature of waterin the tank falls below the selected temperature, the electric circuitto the heating bands, which is controlled by such thermostat, will beclosed, thereby to energize said heating bands and to heat the watercontained in the tank. These heating bands are located around theoutside of the tank and are not immersed in the water. The tanks beingmade of stainless steel or similar non-corroding material are veryefficient heat conductors, so that the heat developed by the heatingbands will readily be transmitted to the contents of the tank.

When the water temperature within the tank rises to or slightly abovethe temperature set 'on the thermostat, the electric circuit to theheating bands will be broken so as to stop the further heating of thewater. Inasmuch as the tanks 1 or 2 are enclosed in efficient insulatingmaterial, heat loss is kept low, and in given instances, the heatdeveloped in the molding press or other equipment, will transmit enoughheat to the water circulated therethrough to fully off-set heat lossesin the circulating system, so that the electrical heating bands areseldom energized, and the main function of the device becomes that oflowering the temperature of the water circulated. However, in otherinstances, the heating bands will be kept energized for a substantialportion of the operating time in order to maintain the circulatingliquid at the required temperature. A thermometer 351 is mounted on thefront panel of the cabinet structure and is connected to a thermometerbulb 30a located in a pipe fitting 3|, which connects the outlet port 32of the pump [4 to the hot water outlet pipe l6. Hence, the temperatureof the water being pumped to the molding press or other apparatus isconstantly registered on the visible dial of the thermometer tofacilitate the determination of existing operating conditions, and toaiford a basis for the exercise of judgment as to adjustment of thesettings of the maximum and minimum temperature limits on thethermostats 24 and 21 respectively.

The tanks I and 2 may be of fairly small capacity, for example, around 1or 1 gallons, so that the total volume of water in the circulatingsystem is not unduly increased by the employment of the circulatingdevice; this also aids in the matter of varying the temperature of thewater, and in maintaining said temperature within one or two degrees ofpredetermined maximum and minimum temperatures.

A suitable air vent 33 is connected to the fitting to, permit the escapeof any air which may separate from the water in the tank. This air ventmay be of any suitable construction of which many are known, being suchas to permit the escape of air without corresponding escape of liquidfrom the system. Relief valves 34 are connected through the fittings I8and 19 into the return pipes II and I2. These relief valves havedischarge pipes 35 extended downwardly to the bottom of the cabinet andare provided as a precautionary measure to relieve pressure in therespective tanks, in the event that some unforseen cause createsexcessive pressure in the system. The bottom of the cabinet is open, orat least may be provided with an opening, so that in the event that anywater is discharged through outlet 35, it Will simply flow to the floor.

To assist in initially charging the tank with water, the pressure reliefvalves 34 may be manually opened through means such as a lever arm 35which may be actuated through a pull rod 37, the latter extending to theoutside of the cabinet and being provided With a handle ring 38. Byopening this pressure relief valve when initially filling the device,the air contained in the tank will be given somewhat more free escapethan through the air vent 33, and the operator of the device willreceive a signal that the tank is full when water issues from the lowerend of the discharge pipe 35. For draining the system, for cleaning andother purposes, a drain pipe 39 is connected to the hot water outletline [5, and extended to the outside of the cabinet where it is providedwith a suitable drain-cock 40. This drain-cock is located in the lowestpart of the system and the air vent and pressure relief valve arelocated in the uppermost part of the system for most advantageousoperation.

The cabinet which encloses and supports the described mechanism may beof any suitable construction, being here represented as consisting ofangle iron frame Work and suitable sheet metal walls supported by theframe work. The instruments, such as the thermostats and thermometers,may be mounted on angularlydisposed panel portions at the front of thecabinet so as to provide clear visibility, and a main switch 4! for eachpump motor may also be mounted on such front panel. The switch 4| may beof the type embodying a signal light which will afiord visual indicationas to the operation of the pump motors. In some instances, it isdesirable that the lower portions of the side walls of the cabinet beformed of suitable, perforated metal or screening, as indicated at 42,to provide ventilation for the interior of the cabinet. The cabinetstructure may be mounted on suitable rollers or caster wheels such asindicated at 43, and a handle may be fastened to the back wall of thecabinet, near the top thereof, to facilitate movement of the cabinetfrom place to place. One part 44 of a separable electrical connector maybe fastened to a suitable part of the cabinet, such as the front wall,for the reception of the companion part of the connector on a flexible,electrical conductor cord of suitable gauge to handle the currentrequired by the motors and heating bands. The electrical connections areof conventional form, bein well understood by skilled electricians,wherefore they are not herein shown.

The described double, or twin, circulating unit provides separatecirculating systems which may be connected to the heating (or cooling)chambers of the upper and lower dies of a plastic or other molding pressand hence, affords independent control of the temperatures of thecooperating dies. In some instances, where only one die is to be heatedin a press, the twin structure here described may serve two, independentpresses, the respective tanks 1 and 2 being then accordingly connectedto the different presses. Either unit may be operated alone, when onlyone unit is required for a given purpose.

The various pipe lines and fittings employed in the structure mayadvantageously be made of non-corroding metals such as brass or bronze,thereby to avoid the development of excessive amounts of scale in thesystem, which would reduce the efiiciency thereof. Inasmuch as each tankis of small capacity, as aforesaid, it may readily be flushed cleanoccasionally, such flushing requiring only a few minutes of time.

The structure described may be used with special advantage in connectionwith the molding of transparent plastic materials which appear torequire somewhat more critical regulation of the temperature than opaqueand colored materials. When molding clear, transparent materials, it isespecially important to avoid scorching of the material, which wouldimpart color and cloudiness, thereby making useless the resultingproducts when clear and transparent products are required. The accuratecontrol of temperature is, of course, advantageous in many situationsand is easily attained by the described structure.

Various changes in the structure may be made while retaining the generalfeatures of the invention described and the principles thereof.

I claim:

1. Water circulating apparatus of the class described, comprising atank, a cold water inlet conduit connected to said tank, means forheating water in said tank, an outlet conduit extending from said tankand adapted to be connected to a temperature controlling chamber or thelike, a return conduit connected to said tank and adapted to beconnected to such chamber for returning temperature controlling liquidfrom such chamber to said tank, a branch conduit extending from saidreturn conduit and having a valve therein normally closing said conduit,and means controlled by the temperature of the fluid for effectingopening of said valve to permit the escape of fluid from said returnconduit and the flow of cold water into said tank through said coldwater inlet.

2. Water circulating apparatus of the class described, comprising atank, a cold water inlet conduit connected to said tank, means forheating water in said tank, an outlet conduit extending from said tankand adapted to be connected to a temperature controlling chamber or thelike, a return conduit connected to said tank and adapted to beconnected to such chamber for returning temperature controlling liquidfrom such chamber to said tank, a branch conduit extending from saidreturn conduit and having a valve therein normally closing said conduit,and thermostatically controlled means responsive to the temperature ofwater in said return conduit for efiecting opening of said valve topermit the escape of hot water from said return conduit, thereby topermit the flow of cold water into said tank through said cold waterinlet.

3. In water heating and circulating apparatus of the class described,the combination of a tank, a water supply conduit connected to said tankand adapted to be connected to a water supply source for deliveringwater to said tank, means for heating water in said tank, outlet andreturn conduits connected to said tank and adapted to be connected to atemperature controlling chamber, a pump connected in one of said lastmentioned conduits for effecting circulation of water from and to saidtank through said outlet and return conduits and a temperaturecontrolling chamber or the like to which said conduits are connected asaforesaid, an air vent connected to an upper portion of said tank andoperative to vent gas from said tank without permitting the escape ofliquid therefrom, and a pressure relief conduit and valve communicatingwith the upper end portion of said tank.

4. In water heating and circulating apparatus of the class described,the combination of a tank, a water supply conduit connected to said tankand adapted to be connected to a water supply source for deliveringwater to said tank, thermostatically controlled electrical means forheating water in said tank, outlet and return conduits connected to saidtank and adapted to be connected to a temperature controlling chamber, apump connected in one of said last mentioned conduits for effectingcirculation of water from and to said tank through said outlet andreturn conduits and a temperature controlling chamber or the like towhich said conduits are connected as aforesaid, an air vent connected toan upper portion of said tank and operative to vent gas from said tankwithout permitting the escape of liquid therefrom, a discharge conduitcommunicating with said return conduit, a valve in said dischargeconduit, means responsive to the temperature of the water returning tosaid tank for actuating said discharge conduit valve to effect dischargeof returning water and, as an incident thereto, delivery of replacementwater to said tank through said water supply conduit, and a pressurerelief conduit and valve communicating with the 'upper end portion ofsaid tank.

GLENN C. BECKER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,931,145 Hall Oct. 17, 19331,983,043 Martin Dec. 4, 1934 2,091,838 Staak Aug. 31, 1937 2,226,526Osterheld Dec. 24, 1940 2,259,401 Tucker et al Oct. 14, 1941

